1995 GMC SIERRA heating

Engine Overheating
YOU will find a coolant temperature gage on your vehicle instrument panel.
If
YOU have a diesel engine, you will also find a low coolant light on your
instrument panel.
lf Steam Is Coming From Your Engine
A CAUTION:
Steam from an overheated engine can burn you badly, even if
you just open the hood. Stay away from the engine if you see or
hear steam coming from it. Just turn it
off and get everyone
away from the vehicle until it cools down. Wait until there is no
sign of steam or coolant before opening the hood.
If you keep driving when your engine is overheated, the liquids
in it can catch fire. You or others could be badly burned. Stop
your engine
if it overheats, and get out of the vehicle until the
engine
is cool.
NOTICE:
If your engine catches fire because you keep driving with no
coolant, your vehicle can be badly damaged. The costly repairs
would not be covered by your warranty.
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Canadian Fuels
Diesel-powered trucks are now equipped with emission control systems that
require the use of diesel fuel with low-sulfur
(.05% by weight) content.
Both low- and higher-sulfur fuels will be available
in Canada. Only
low-sulfur diesel fuels are available
in the United States. It is important that
diesel-powered trucks are refueled with low-sulfur fuel. Use of fuels with
higher-sulfur content will affect
the function of the emission components
and may cause reduced performance, excessive smoke and unpleasant odor.
Cold Weather Operation
Follow the instructions listed previously under the heading “What Fuel to
Use.”
If you’re driving
in very toold temperatures and can’t get a “winterized”
Number
2-D that has been adapted to cold weather or a Number 1-D, you
can
use one gallon of kerosene for every two gallons of diesel fuel. Once
you add the kerosene, run your engine for several minutes
so the fuels will
mix. Add kerosene only when the temperature falls below 0°F (-1 S”C),
because the fuel economy of kerosene isn’t as good as that of diesel fuel.
NOTICE:
Never use home heating oil or gasoline in your diesel engine. \
They can cause engine damage.
In cold weather, your fuel filter may become clogged (waxed). To unclog it,
warm the filter to between
32°F and 50°F (OOC to 10°C). You won’t need
to replace
it.
Water in Fuel
Sometimes, water can be pumped into your fuel tank along with your diesel
fuel. This can happen
if a service station doesn’t regularly inspect and clean
its fuel tanks, or
if it gets contaminated fuel from its suppliers.
If this happens, a WATER
IN FUEL light will come on. If it does, the excess
water must be drained. Your dealer can show
you how to do this.
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NOTICE:
If there is water in your diesel fuel and the weather is warm or
humid, fungus and bacteria can grow in the fuel. They can
damage your fuel system. You'll need a diesel fuel biocide to
sterilize your fuel system. Your dealer can advise
you if you ever
need this.
If your fuel tank needs to be purged to remove water, see your
dealer or a qualified technician. Improper purging can damage
your fuel system.
Running Out of Fuel (Diesel Engines)
If the engine stalls and you think that you've run out of fuel, do this:
First, open the fuel filter air bleed valve.
Briefly crank the
engine and have
someone watch the
bleed valve. If there is
air, then you are
probably
out of fuel.
To restart your engine:
I. If you're parked on a level surface, add at least two gallons of fuel.
However, if you're parked
on a slope, you may need to add up to five
gallons of fuel.
2. With the air bleed valve open, turn your ignition key to START for 10
to
15 seconds to crank (but not start) your engine. Wait one minute
between intervals
of cranking to allow the starter motor to cool.
Overheating the starter motor could damage it. Keep doing this until
you can just see some clear fuel at the air bleed valve. (If, during this
step, the engine starts, turn the ignition off and close the valve before
restart.)
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If the differential is at operating temperature (warm), add enough lubricant
to raise the level to the bottom
of the filler plug hole.
If the differential is cold, add enough lubricant to raise the level to
1/2 inch
( 12 mm) below the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Engine Coolant
The following explains your cooling system and how to add coolant when it
is low. If you have a problem with engine overheating, see “Engine
Overheating”
in the Index.
The proper coolant for your vehicle will:
Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 262°F (128°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning gages work as they should.
What to Use
Use a mixture of one-half cleun water (preferably distilled) and one-half
antifreeze that meets “GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
Specification 6038-M.” Use GM Coolant Supplement (Sealer) with a
complete coolant flush and refill. If you use this mixture. you don’t need to
add anything else.
A CAUTION:
Adding only plain water to your cooling system can be
dangerous. Plain water, or some other liquid like alcohol, can
boil before the proper coolant mix will. Your vehicle’s coolant
warning system
is set for the proper coolant mix. With plain
water or the wrong mix, your engine could get too hot but
you
wouldn’t get the overheat warning. Your engine could catch fire
and you or others could be burned. Use
a 50/50 mix of clean
water and
a proper antifreeze.
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To Check Coolant
A CAUTION:
Turning the surge tank pressure cap when the engine and
radiator are hot can allow steam and scalding liquids to blow out
and burn you badly. Never turn the surge tank pressure cap
-
even a little - when the engine and radiator are hot.
When your engine is cold, the coolant level should be at the COLD mark, or
a little higher.
If this light comes on, it means you’re low on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix ut the surge tmk, but only
when the engine is cool. If the surge tank is empty, see “Engine
Overheating”
in the Index for the proper fill procedure.
A CAUTION:
You can be burned if you spill coolant on hot engine parts.
Coolant contains ethylene glycol, and
it will burn if the engine
parts are hot enough. Don’t spill coolant on a hot engine.
When replacing the pressure cap, make sure it is tight.
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Radiator Pressure Cap - Gasoline Engine
The radiator pressure
cap must be tightly
installed with
the
arrows on the cap
lined up with the
overflow tube on the
radiator filler neck.
NOTICE:
Your radiator cap is a 15 psi (105 kPa) pressure-type cap and
must be tightly installed to prevent coolant loss and possible \
engine damage from overheating. Be sure the arrows
on the cap
line up with the overflow tube on the radiator filler neck.
Surge Tank Pressure Cap - Diesel Engine
The surge tank
pressure cap must be
tightly installed with
the arrows on the cap
lined up with the top
tube of the coolant
surge tank.
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NOTICE:
Your surge tank pressure cap is a unique 15 psi (105 kPa)
pressure-type cap for use with surge tank cooling systems only.
It must be tightly installed to prevent coolant loss and possible
engine damage from overheating. Be sure the arrows on the cap
line up with the top tube of the coolant surge tank.
Thermostat
Engine coolant temperature is controlled by a thermostat in the engine
coolant system. The thermostat stops the flow
of coolant through the
radiator until the coolant reaches a preset temperature.
When you replace your thermostat, an AC@ thermostat is recommended.
Power Steering Fluid
How To Check Power Steering Fluid
When the engine compartment is cool, unscrew the cap and wipe \
the
dipstick with a clean rag. Replace the cap and completely tighten it. Then
remove the cap again and look at the fluid level on the dips\
tick.
The level should be at the
FULL COLD mark. Add enough fluid to bring
the level
up to the mark.
A fluid loss in this system could indicate a problem. Have the system
inspected and repaired.
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Tires
We don’t make tires. Your new vehicle comes with high-quality tires made
by a leading tire manufacturer. These tires are warranted by the tire
manufacturers, and their warranties are delivered
with every new vehicle. If
your spare tire is a different brand than your road tires, you will have
a tire
warranty folder from each
of these manufacturers.
A CAUTION:
Poorly maintained and improperly used tires are dangerous.
Overloading your tires can cause overheating as a result of too
much friction. You could have an air-out and a serious
accident. See “Loading Your Vehicle” in the Index.
Underinflated tires pose the same danger as overloaded tires.
The resulting accident could cause serious injury. Check all
tires frequently to maintain the recommended pressure. Tire
pressure should be checked when your tires are cold.
Overinflated tires are more likely to be cut, punctured, or
broken by
a sudden impact, such as when you hit a pothole.
Keep tires
at the recommended pressure.
Worn, old tires can cause accidents. If your tread is badly
worn, or if your tires have been damaged, replace them.
Inflation - Tire Pressure
The Certification/Tire label which is on the rear edge of the driver‘s door, or
on the incomplete vehicle document in the cab, shows the correct inflation
pressures for your tires, when they’re cold. “Cold“ tneans your vehicle
has
been sitting for at least three hours or driven no more than a mile.
You can operate some vehicles at reduced inflation pressures only when
you’ll be carrying reduced loads. On those vehicles, the minimum cold
inflation pressures for
a typical reduced load are printed on the “Improved
Ride Tire Pressure” label located on the driver’s door. Weigh the vehicle to
find the load on each tire and see the label for the minimum cold inflation
pressures for that load.
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